The purposes of the study are to determine 1) the effects of a range of doses of BRL 32872A infused intravenously on a) electrophysiologic parameters and surface ECG derived parameters including QT dispersion and heart rate and b) hemodynamic parameters. 2) To further define the safety of IV BRL 32872A through observations of adverse experiences, vital signs, laboratory test abnormalities and changes in ECG. 3) To describe a relationship between the dose of BRL 32872A, the plasma concentration of BRL 32872A and pharmacodynamic endpoints.